Relieve tension and stiffness
Targeted stretches for the neck and shoulders, where desk work and phone use concentrate the most tension.
Looking down at a phone increases the effective load on the neck substantially, because the head is heavy and the further forward it sits the more leverage it exerts. Raising the screen is usually more effective than any stretch.
These are general wellbeing exercises, not medical advice. If you have a health condition, are recovering from injury, or find that an exercise causes pain rather than mild discomfort, speak to a qualified professional rather than working through it.
Because the head is heavy and tilting it forward multiplies the load on the neck considerably. Raising the phone toward eye level reduces that load far more than stretching afterwards does.
Full circles are generally discouraged, particularly the backward portion. Gentle half-circles to the front give the same benefit with less risk.
Roughly with the top of the screen at eye level, so your gaze falls slightly downward without tilting your head forward.